Another good Tool for VPI Table

I'm very familiar with the collimation of Telescope Optics, owning, and having owned many different optical designs over the past 35 years.

Just like Aligning a Optical Mirror, or Lens-Corrective Lens, I found that as one rotates the Platter, one can easily see via Dial indicator, where the high-low spots on the Platter were, and with those areas facing towards the Dial Indicator, one could make the necessary adjustments, of up, or down.

Just like with Optics, I found just a careful slight nudge of the Adjustment Screw, practically a 1/00th of a turn, to where the Screw just began to turn, was almost too groos of an adjustment.

Almost similar (but not as hard) to using a MintLP Protractor, where one goes back, and forth repeatedly, to get the adjustment perfectly set, I concluded that any imperfections were due to reasons other than errors with the adjustment, just as imprections in the Platter machining itself, errors of the Dial Caliper, or lack of getting a perfect final adjustment.

I'll state further, that I made a Paper Mat from an old LP Paper Inner Sleeve to protect the Acrylic Platter's Surface from possibly being scratched by the Dial Indicator's Metal Tip. How much deviance from being true, the makeshift Paper Mat was, I have no idea!?
Mark

Dear Mark, you excited my curiosity and I ordered one . I will try to tweak it for better turntable platter use, as replacing the metal tip by some kind of roller.
But I will inform you. It is an useful device for any TT to check bearing wear. I keep you informed.
Jean.

Jean, The Metal Tip on my Dial Indicator looks like a small Ball Bearing, but it doesn't roll. As a friend mentioned to me, it would as well be a simple matter of covering the tip with a small piece of Cellophane Tape to prevent any acratching of Platter Surface. This would probably insure better accuracy rather than a makeshift Platter Mat.

I would assume VPI would do this service if you sent Platter-Bearing, but the shipping cost alone would probably equate to the cost of the Tools, and then you have them for future use.

The Vacuum Base Stand that I ordered with the Indicator from Harbor Freight is a quite massive, and heavy piece, and very nicely built. The Dial Indicator is as well, a quality piece. I feel I got more than my money's worth with this tool.

I would assume everytime I remove Platter for Lubrication service of Bearing, that getting the Platter positioned exactly again on the Bearing Flange is virtually impossible. Mark

Holy moley Jean, what a system! Very unusual I must say, I never seen such a configuration on a Turntable.
Just awesome! Mark

Thank you Mark. This is a project started with the rediscovery of rim drive benefits over belt drive, but no upgrade from VPI for single motor, so I tried with spare parts and the result is well superior compared to one platter belt drive. The project is so rewarding that I continue with better damping and a new plinth will replace the acrylic one, a sandwich slate/aluminium/carbon full size plinth with a cool design. As always I have to try and compare before adopting a new step in progress. Also mylar belt drive with modified motor rubber shaft soon coming.
The tool you suggest on this thead is essential for proper platter adjustment.
Thanks for the input !
Jean.